﻿using System;
using RGB.NET.Core;
using SkiaSharp;

namespace Artemis.Core;

/// <summary>
///     A static class providing <see cref="SKColor" /> extensions
/// </summary>
public static class SKColorExtensions
{
    /// <summary>
    ///     Converts hte SKColor to an RGB.NET color
    /// </summary>
    /// <param name="color">The color to convert</param>
    /// <returns>The RGB.NET color</returns>
    public static Color ToRgbColor(this SKColor color)
    {
        return new Color(color.Alpha, color.Red, color.Green, color.Blue);
    }

    /// <summary>
    ///     Interpolates a color between the <paramref name="from" /> and <paramref name="to" /> color.
    /// </summary>
    /// <param name="from">The first color</param>
    /// <param name="to">The second color</param>
    /// <param name="progress">A value between 0 and 1</param>
    /// <returns>The interpolated color</returns>
    public static SKColor Interpolate(this SKColor from, SKColor to, float progress)
    {
        int redDiff = to.Red - from.Red;
        int greenDiff = to.Green - from.Green;
        int blueDiff = to.Blue - from.Blue;
        int alphaDiff = to.Alpha - from.Alpha;

        return new SKColor(
            ClampToByte(from.Red + redDiff * progress),
            ClampToByte(from.Green + greenDiff * progress),
            ClampToByte(from.Blue + blueDiff * progress),
            ClampToByte(from.Alpha + alphaDiff * progress)
        );
    }

    /// <summary>
    ///     Adds the two colors together
    /// </summary>
    /// <param name="a">The first color</param>
    /// <param name="b">The second color</param>
    /// <returns>The sum of the two colors</returns>
    public static SKColor Sum(this SKColor a, SKColor b)
    {
        return new SKColor(
            ClampToByte(a.Red + b.Red),
            ClampToByte(a.Green + b.Green),
            ClampToByte(a.Blue + b.Blue),
            ClampToByte(a.Alpha + b.Alpha)
        );
    }

    /// <summary>
    ///     Darkens the color by the specified amount
    /// </summary>
    /// <param name="c">The color to darken</param>
    /// <param name="amount">The brightness of the new color</param>
    /// <returns>The darkened color</returns>
    public static SKColor Darken(this SKColor c, float amount)
    {
        c.ToHsl(out float h, out float s, out float l);
        l *= 1f - amount;
        return SKColor.FromHsl(h, s, l);
    }

    private static byte ClampToByte(float value)
    {
        return (byte) Math.Clamp(value, 0, 255);
    }
}